see if your bike shop has a barrel of take-off saddles from new bikes. most new (low to mid range) bikes come with a factory saddle, and lots of them are replaced before the bike leaves the shop.

or, there's a guy in houston that buys them bulk from the shops and sells them cheap on CL. i bought a new stock bianchi saddle for $20 from this guy and it's way better than the old broken in selle that came with my used 90's bianchi.